Improving Water Quality; bringing back the bayous

Those who have lived in the Pensacola area for many years will remember the days when our local bayous were places people water skiied, kids learned to swim, and fishermen brought home plenty of speckled trout. But today we see little of this. Water quality within our bayous has declined to a point that the general public is concerned about recreation within them and most use them as access to larger bodies of water where they can enjoy water activities.

What Happened?

The mouth of Bayou Grande near Navy Point; a popular recreation location

Those who lived here when things were better say they first noticed problems when new roads and subdivisions were built in the 1950’s. Decline in water clarity was one of the first things they noticed. This was followed by a loss of submerged grasses, fish kills, and an increase in health advisories due to high levels of bacteria. These new subdivisions cleared much of the native vegetation in the neighborhoods and along the water front. The loss of vegetation and new roads allowed for more runoff to reach the bayous. Much of this runoff was in the form of leaf litter, twigs, animal waste, and maybe even carcasses of dead creatures. Once reaching the water these organics are broken down by bacteria into forms of nitrogen and phosphorus that can be utilized by aquatic plants and phytoplankton. This increase in plants will produce more oxygen, but they also consume oxygen in the evening. The high demand for oxygen in the evening can cause dissolved oxygen levels to decline to a point where aquatic life begins stressing; we now say the water is hypoxic. To add to the problem people began to have the desire for lawns of non-native grasses which require fertilizer and watering; thus increasing the nutrient load on the system and an increase in hypoxia. This eutrophication process was a major contributor to the fish kills that the bayous were experiencing.

In addition to nutrients, animal waste could be found in the stormwater. Animal waste can contain pathogensthat could be a serious risk to public health. Scientists monitor the concentration of these pathogenic bacteria by using a group of indicator bacteria called fecal coliformbacteria. High levels of these fecal coliforms indicate that a potential health risk could be present and the Escambia County Health Departmentwould issue a health advisory for that body of water. A study showed that the concentration of fecal coliforms increased in areas where coastal development increased, connecting them to stormwater problems.

Marine Science Academy students from Washington High School measuring chlorophyll in Bayou Texar; photo: Ed Bauer

So What Can We Do?

We will probably never be able to get the bayous back to the state they were in before the development boom of the mid-20th century but there are few things we can do. First, the reason the nutrients and fecal coliforms increased was an increase in runoff. This increase was due to road construction and loss of vegetation. We cannot do much about the roads but we can rethink how we landscape our yards and waterfront property.

The Florida Friendly Yards Programis one that helps residents with selecting plants and landscaping features that require little or no fertilizer or water. This not only reduces the runoff but saves the homeowner money. Rain barrels and rain gardens are also methods that can both reduce water runoff and save money. For more information on this program you can contact Carrie Stevenson at the Escambia County Extension Office; 850-475-5230 or ctsteven@ufl.edu.

Shoreline vegetation can be restored through the Living Shoreline Program. In this program the Florida Department of Environmental Protection works with the homeowner on designing a shoreline marsh and/or oyster reef project. Living Shorelines utilize plants that remove much of the nutrients found in runoff and oysters are known to filter 50 gallons of water per hour, reducing turbidity typically caused by runoff. Not only do Living Shorelines reduce nutrient runoff, they also reduce erosion caused by wave energy. For more information on Living Shorelines contact Beth Fugate at beth.l.fugate@dep.state.fl.us.

Planting a Living Shoreline on Bayou Texar in Pensacola; photo: Florida Department of Environmental Protection

We hope you will consider using one of these programs to help improve the water quality within our bayous. If you are interested in having a presentation on these programs contact Rick O’Connor at the Escambia County Extension Office; 850-475-5230 or roc1@ufl.edu.